360 



LOWER VERTEBRATES. 



possibly be regarded as a northern variety of the more tropical Jioa constrictor, 

 though the scales of the head are ratlier large. The general color is brownish, with a 

 dorsal series of quadrangular brown spots, which is separated from the smaller spots 

 of the flanks by a pair of light lateral lines. 7>. constrictor, though properly an inhabi- 

 tant of Brazil, is represented in Central America by a variety, isthmica. Along the 

 back is a series of transverse brown bands, each connected with the marks of the 

 flanks by a latero-posterior isthmus, and along each side of the belly is a series of more 



^^"^"^ W H I it w vA'i V 7'"/ .?■ ' 





J" 



Fig. 212. — Boa constrictor, 



or less broken, irregular sjiots of a black color. B. mexiccma is allied to B. imperator. 

 B. constrictor, proper, iidiabits the more tropical ]iortions of South America, though 

 travelers from all parts of the world have almost in\ariably described large serpents 

 which have come under their notice as 'Boa-constrictors,' rendering it extremely 

 difHcult to determine acurately what species they are describing, and bringing the 

 name to so gener.al a use that it has almost lost the primary significance given it by 

 its original propounder, Linne. 



